Multivariate Exploratory Analysis of the Bulgarian Soil Quality Monitoring Network

Area of Science:

• Environmental Science
• Soil Science
• Geochemistry

Background:

• Soil quality is crucial for ecosystem health and agricultural productivity.
• Assessing soil quality requires comprehensive analysis of various indicators.
• Understanding spatial variations in soil properties is essential for effective land management.

Purpose of the Study:

• To evaluate soil quality across Bulgaria using a suite of key indicators.
• To identify major factors influencing soil quality patterns using data mining techniques.
• To map soil quality and pinpoint areas needing enhanced monitoring for potentially toxic elements (PTEs).

Main Methods:

• Utilized primary nutrients (C, N, P), acidity (pH), clay content, and potentially toxic elements (PTEs) as soil quality indicators.
• Applied chemometric and geostatistical methods, including principal component analysis (PCA) and hierarchical cluster analysis (HCA).
• Developed spatial distribution maps of identified soil quality patterns.

Main Results:

• Five latent factors explained approximately 70% of the total data variance: mountain soil, geogenic, ore deposit, low nutrition, and mercury-specific factors.
• Hierarchical cluster analysis confirmed distinct soil quality patterns.
• Spatial mapping revealed specific regions, often near industrial facilities and intensive agriculture, requiring focused PTE monitoring.

Conclusions:

• The study successfully characterized Bulgarian soil quality by identifying key influencing factors and their spatial distribution.
• The identified patterns and maps provide a basis for targeted environmental monitoring and management strategies.
• Specific agricultural regions near industrial sources require prioritized monitoring for phytoavailable PTEs to mitigate risks.